In general, a refrigerator is one of the living necessaries which preserves food fresh for a predetermined period, by lowering a temperature of a freezing chamber or a refrigerating chamber by repeating a refrigeration cycle of compressing, condensing, expanding and evaporating refrigerants.
The refrigerator has a refrigeration cycle including basic components such as a compressor for compressing refrigerants into high temperature high pressure gas refrigerants, a condenser for condensing the refrigerants from the compressor into high temperature high pressure liquid refrigerants, an expansion valve for decompressing the refrigerants from the condenser into low temperature low pressure liquid refrigerants, and an evaporator for maintaining a low temperature in a freezing chamber or a refrigerating chamber, by absorbing heat from the freezing chamber or the refrigerating chamber by evaporating the refrigerants from the expansion valve into low temperature low pressure gas refrigerants.
FIG. 1 is a schematic front perspective view illustrating a conventional side-by-side type refrigerator, and FIG. 2 is a structure view illustrating a refrigeration cycle applied to the refrigerator of FIG. 1.
The conventional side-by-side type refrigerator in which a freezing chamber and a refrigerating chamber are disposed side by side will now be described with reference to FIGS. 1 and 2. A refrigeration cycle including a compressor 12, a condenser 14, an expansion valve 16 and an evaporator 18 is built in an inner wall, for generating cool air by the evaporator 18. The freezing chamber F maintaining about −18° C. by sucking most of the cool air, and the refrigerating chamber R maintaining about 0 to 7° C. by sucking part of the cool air are disposed side by side at both sides of a main body 2.
The refrigeration cycle includes basic components, and thus explanations thereof are omitted.
Here, the freezing chamber F and the refrigerating chamber R are divided by a cross wall 4. Part of the cross wall 4 is opened so that the cool air can flow between the freezing chamber F and the refrigerating chamber R.
The evaporator 18 is installed on the inner wall in the freezing chamber F, and a blast fan 22 is installed at the upper portion of the evaporator 18, for sending cool air generated in the evaporator 18 to the freezing chamber F or the refrigerating chamber R. Generally, an axial flow fan for sucking and discharging cool air in an axial direction is used.
The freezing chamber F and the refrigerating chamber R compose a cool air circulation structure for circulating cool air near the evaporator 18 through the freezing chamber F and the refrigerating chamber R by the operation of the blast fan 22, and returning the cool air to the evaporator 18.
The operations of the components of the refrigerator are controlled by a microcomputer (not shown). The microcomputer controls the whole components so that a temperature Tf of the freezing chamber F and a temperature Tr of the refrigerating chamber R can reach a set freezing temperature Tf0 and a set refrigerating temperature Tr0 setting by the user or automatically set.
In the conventional refrigerator, when a load is applied, the compressor 12 is operated according to a control signal from the microcomputer, and refrigerants are circulated though the compressor 12, the condenser 14, the expansion valve 16 and the evaporator 18, for cooling air near the evaporator 18 and generating cool air.
In addition, the blast fan 22 is operated according to a control signal from the microcomputer, so that most of the cool air near the evaporator 18 can be supplied to the freezing chamber F and part of the cool air can be supplied to the refrigerating chamber R. The cool air circulated in the freezing chamber F and the refrigerating chamber R to have a high temperature is resupplied to the evaporator 18.
In the conventional refrigerator, one evaporator 18 is installed in the freezing chamber F, and the cool air heat-exchanged through the evaporator 18 is partially distributed and supplied to the refrigerating chamber R on the passage of the freezing chamber F. Accordingly, when the inside temperature of any one of the freezing chamber F and the refrigerating chamber R does not satisfy the set freezing temperature Tf0 or the set refrigerating temperature Tr0, the compressor 12 and the blast fan 22 are operated to lower the temperature, thereby increasing power consumption or supercooling food.
For example, when the temperature Tf of the freezing chamber F reaches the set freezing temperature Tf0, if the temperature Tr of the refrigerating chamber R does not satisfy the set refrigerating temperature Tr0, the temperature Tr of the refrigerating chamber R must be lowered to reach the set refrigerating temperature Tr0 by operating the compressor 12 and the blast fan 22. Here, the cool air is also supplied to the freezing chamber F, to unnecessarily lower the temperature Tf of the freezing chamber F. In addition, power consumption increases.
On the other hand, when the temperature Tr of the refrigerating chamber R reaches the set refrigerating temperature Tr0, if the temperature Tf of the freezing chamber F does not satisfy the set freezing temperature Tf0, the temperature Tf of the freezing chamber F must be lowered to reach the set freezing temperature Tf0 by operating the compressor 12 and the blast fan 22. The cool air is also supplied to the refrigerating chamber R, to unnecessarily lower the temperature Tr of refrigerating chamber R. Moreover, food is supercooled.
In the conventional refrigerator, part of the cool air from the evaporator 18 is distributed to the refrigerating chamber R. A volume of the cool air distributed to the refrigerating chamber R is relatively smaller than a volume of the cool air distributed to the freezing chamber F. Therefore, a cooling speed of the refrigerating chamber R is reduced, to unnecessarily operate the compressor 12.
For example, when the temperature Tr of the refrigerating chamber R does not reach the set refrigerating temperature Tr0, the compressor 12 is operated until the temperature Tr of the refrigerating chamber R reaches the set refrigerating temperature Tr0. Accordingly, an excessive load is applied to the compressor 12 to reduce the temperature of the evaporator 18 lower than the temperature Tf of the freezing chamber F.